NUCLEAR RETINOIC ACID RECEPTORS IN HEAD/NECK CARCINOGENESIS & CHEMOPREVENTION

核视黄酸受体在头颈癌发生中的作用

• 批准号: 6300365
• 负责人: REUBEN LOTAN
• 金额: $ 24.59万
• 依托单位: UNIVERSITY OF TX MD ANDERSON CAN CTR
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-03-22 至 2000-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6300365
• 关键词: antireceptor antibody; antisense nucleic acid; athymic mouse; carcinogenesis; cell differentiation; cell growth regulation; chemoprevention; clinical research; flow cytometry; head /neck neoplasm; human subject; in situ hybridization; neoplastic cell; northern blottings; preneoplastic state; prognosis; receptor expression; retinoid binding proteins; retinoids; squamous cell carcinoma; tissue /cell culture; transcription factor; transfection /expression vector; vitamin metabolism; western blottings

Vitamin A and some of its analogs (retinoids) prevent squamous differentiation of normal nonkeratinizing epithelial cells in vivo and in vitro and suppress oral premalignant lesions (leukoplakia) in man and carcinogenesis in the upper aerodigestive tract in experimental animals. The mechanism(s) by which retinoids exert these effects is not known. Nuclear retinoic acid receptors (RARs) function as ligand-activated trans-acting transcription modulating factors and mediate the effects of retinoids on the expression of certain genes. The hypotheses underlying this project are: (A) Retinoids' ability to suppress malignant cells, and (B) These effects result from changes in gene expression mediated via nuclear retinoid receptors. The objectives of this project are: To determine the relevance of the RARs for mediation of the effects of retinoids on the growth and differentiation of human head and neck squamous cell carcinoma (HNSCC) cells in vitro. Three HNSCC cell lines before and during treatment with 13-cis retinoic acid (13cRA) in vitro and biopsies of human oral mucosa and leukoplakia lesions taken from patients before and during treatment with 13cRA will be used to: (a) Determine the presence and level of RAR-alpha, RAR-beta, RAR-gamma, and RXR-alpha in HNSCC cells at the mRNA level (by Northern blotting) and at the protein level (by immunoblotting and radioactive retinoid binding); (b) Determine whether the expression of any of the RARs is modulated in HNSCC cells by retinoid treatment; (c) Determine whether the level of any of the RARs before and after retinoid treatment is related to the responsiveness of the HNSCC cells to the effects of 13cRA on squamous cell differentiation markers transglutaminase, involucrin, and K1 keratin at the mRNA level and at the protein level; (d) Determine whether blocking the expression of one or more of the RARs by antisense oligonucleotides or mRNA will inhibit any of the effects of 13cRA on the HNSCC cells; (e) Determine the presence and level of RARs and the expression of transglutaminase, involucrin, and K1 keratin in "normal" mucosa cells and in biopsies from oral leukoplakia lesions before and after treatment with 13cRA in vivo by in situ hybridization with nucleotide probes for RARs' and differentiation markers' mRNAs, and immunohistochemical analysis with antibodies to each receptor and differentiation marker. These studies are expected to provide important information on the involvement of RARs in the mechanism of action of retinoids on HNSCC in vitro and possibly on premalignant oral epithelial cells in vivo.

维生素A及其某些类似物（类视丁素）防止鳞状 在体内和 人体体外和抑制口腔前病变（leukoplakia） 实验动物的上层机场消化道中的致癌作用。 类视黄素发挥这些作用的机制尚不清楚。 核视黄酸受体（RARS）起着配体激活的作用 跨作用转录调节因子并介导效果 类维生素类似于某些基因的表达。 假设 该项目的基础是：（a）类维生素类似于抑制的能力 恶性细胞和（b）这些作用是由于基因的变化而引起的 通过核性类维生素类受体介导的表达。 目标的目标 该项目是：确定RAR的相关性 类视网膜类似对人类生长和分化的影响 头颈部鳞状细胞癌（HNSCC）细胞体外。 三 HNSCC细胞系在用13 cis视黄酸治疗之前和期间 （13cra）人类口腔粘膜和白细胞的体外和活检 在13cra治疗之前和治疗期间从患者中采取的病变将 用于：（a）确定rar-alpha的存在和水平，rar-beta， 在mRNA水平的HNSCC细胞中的RAR-GAMMA和RXR-ALPHA（由Northern 斑点）和蛋白质水平（通过免疫印迹和放射性 视网膜类似的结合）; （b）确定是否表达 通过视网膜类动物治疗在HNSCC细胞中调节RARS； （c）确定 视网膜类似治疗前后的任何ras的水平是否 与HNSCC细胞对 13克拉在鳞状细胞分化标记上转谷氨酰胺酶， 在mRNA水平和蛋白质水平上的含蛋白和K1角蛋白； （d）确定是否阻止了一个或多个RAR的表达 通过反义寡核苷酸或mRNA将抑制任何效果 HNSCC细胞上的13克拉； （e）确定的存在和水平 RARS和转谷氨酰胺酶，依赖蛋白和K1角蛋白的表达 在“正常”粘膜细胞和口服白细胞病变的活检中 通过原位杂交用13cra在体内处理前后 用核苷酸探针用于RARS和分化标记的mRNA，以及 免疫组织化学分析，用每个受体抗体， 分化标记。 这些研究有望提供重要的 有关RAR参与行动机理的信息 HNSCC上的视网膜类似于体外，可能是口服前上皮 细胞体内。